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No, it's not possible to break a fast safely without putting weight on again, because part of the weight loss is artificial, namely the contents of your intestines, digestive system etc.
To minimise weight gain, eat a high nutrient plant based diet after the fast. A good plan would be Dr Fuhrman's eat to live plan, which tends to be low in starchy foods.
After the initial weight gain you will find that you start to lose weight anyway on a plant based diet (assuming you are overweight, don't know what your BMI is), and add a few more starchy foods and exercise and you'll be losing quicker than a fast.
However if you wish to fast again, the period between fasts is at least as long as the fast itself, so in your case 7 days. When I was fasting to lose weight, I allowed about twice as long, I found that I lost weight more quickly on a fast after I started to lose weight naturally by eating.
You can't push it too quickly as there are issues with metabolic set point. When fasting, I lost on average 5
pounds a month, and when eating, 8
pounds a month. These days I prefer eating because it's quicker and there is no weight gain at the end, plus you don't get tired etc.
Good luck :)